ca18det nightmare

[euroboy]

ok where do i start?I know a lot of this stuff was covered before but i can't access it so plz don't be pissed if this is a repost.

well 200 sx ca18det, installedthe car fell underpowered yesterday. Was boosting healthy but it wasn't going like it's supposed to. My ca18et was faster. So at idle my car stubbles a lot, goes to almost dead revives again.I am running an vented bov so that might be a problem.So i changed the spark plugs today with ngk from ca18et exhaust side .044in gap. While at it did a cr test. Not oil in the chambers just tester in and go.145-150 accross...decent...anyhows maf died tonight...wondering if the 240 maf would be a replacemet?while engine running took off the oil dip stick and put my finger in there, there is some pressure, so i think my pcv needs to be replaced too(unless this is wrong what i was doing)my knock sensor i dunno if it's in out....i am running no downpipe so i was wondering if these engines need some backpressure? Even the turbo ones don't need it...one last thing after i put the new plugs in the engine didn't want to idle properly for a few minutes but it came back to life....

any opinion and advice is welcomeBess

[iliketocrash]

well i had a very similar problem and it ended up being that my knock sensor wasn't wired up. before i connected it my car was running like a dog. it would boost up to about 8psi but it wouldn't even make a difference. after i wired it up it ran 100% better.

[euroboy]

what about the pcv, that wouldn't make a difference?BOV?Anything like that?

[r34 gtr]

well, i would definately check your pcv to make sure its working as it should. im running an open bov and my car runs (ran) like a dream. your compression is fine (a little low but its all even and my car hauled ace with 125-140 comp.). knock sensors on the CA rarely go out but i would definately make sure its got the right voltage and is working correctly.

as for the MAFS, the ka24e one works but other than that youll need a CA replacement or a safc or something to allow you to run a different one.

the downpipe (or the lack thereof) should do nothing but make the car louder, though it can mess with the readings your o2 sensor is getting, causing you to run rich.

make sure the o2 sensor, pcv, aacv, knock sensor and maf are working correctly and getting the right amount of power. the pcv, aacv and o2 sensor are all on the same circuit, mine wasnt getting the right voltage and so the car was only putting out 125whp. 151whp on 10psi.

- tim

[euroboy]

ok knock sensor is that niple thing aboe the starter.....well that was unplugged and the harness is complete so i haven't any extras....unless it's the stupid plug with a boot around it.i will check and seei guess hitting the scrap for a ka24e maf.....they are 4 wire mafs right?let you guys know how it turns out

[r34 gtr]

hey, if you need a ka24e maf ive got one at my house. gimme an address and i can send it out uum, tuesday i guess. stupid holiday messing stuff up. dont know how soon you need it. as for the knock sensor, you need to hard wire it yourself. get the plug off the thing and wire it straight to the ecu. youll need it hooked up for the car to run properly. dont worry, it only takes 10-15 minutes.

- tim

[euroboy]

thanks for the offer man but i got 4 mafs from a 20 min trip to the junkyard here ......

about the knock sensor i need to unscrew it and run hard wire directly to the ecu?where in the ecu i should run it?directly to a pin out or to a main like ecu power or something like that?plus should it have a relay since the ecu only sends out small jolts and it should be like a step up or down transormer to convert it?if anyone has done it plz let me know....

[euroboy]

ok the ka24e maf has a 3 wire plugca18det has a 4 wire plugwhat do you guys do to make this one work?swap the top part of the maf?

[iliketocrash]

which side of the knock sensor wasn't plugged in? the plug that goes directly onto the end of the sensor? if that was it then you still have to manually hard wire the other end into your stock KA harness. pull your ECU codes and find out what's goin on.

[euroboy]

i have a 200sx s12.....what i did is get the plug from my ca18et and run a hard wire from the knock sensor to the ecu pin out 23....i hope i am right i will check the voltmeter tomorrow see where i am at. FSM says 3-4V

[r34 gtr]

this was 5 days ago and no update as to if it worked or not?! or did you post it elsewhere...

- tim

[euroboy]

no what i did was pointlessgotta find another route to hook it up

[r34 gtr]

hmm. i looked at it on the fsm. it should hook up like that.. also the o2 sensor may not be getting a correct reading because you dont have a dp on there. might be mixing with the outside air, so the ecu thinks its too lean. is the car smoking at all?

- tim

[euroboy]

yep it's smoking all right

[euroboy]

yeah all these little things only change the outcome JUST a littlewhen i fixed some bugs it was idling good and running good.It happened under load at 9 pounds of boost.after that the car wouldn't idle

[Loofee95SE]

ok so, I also got a knock sensor code, look under the intake manifold, theres the thing that looks like a spark plug with 1 wie connector ( wire color is white) and it's plug on.so can it be that the wire is cut somewhere i don't know?? so hard wire to ecu pin #23 right?? some body confirmthis for me. C

[Trigger]

yeah if your getting a knock sensor code then try going from the sensor itself and wiring it that way

Tim

[r34 gtr]

yeah. pin 23 on the ecu.

euroboy, i would try slapping a dp on it and seeing if it does anything. might be nothing wrong, just that the o2 sensor is getting a crappy reading.

- tim

[euroboy]

i thought the knock sensor wire was green with white patches?

[Bizz]

my knock sensor wire is straight white at the plug, and grey shielded where it joins the harness.